The Mystik is safe and so is the area that it's located in. I have stayed there many times and prefer it over many other places I have stayed at previously.
I used to stay at the Hotel La Colonia and Hotel Freeman, both located in the Colonial Zone, and I used to stay at the Jaragua a lot. Although these hotels are okay more or less,the area they're in has no parking except for on the street & often you'll be forced to park far from the hotel due to a lack of parking spaces. The Jaragua has plenty of parking, but it costs more than the Mystik. The Mystik has it's own parking lot also, but is more affordable.
It's cheaper than the Jaragua and just a two minute walk away. It's a great, safe place to stay.